Organo-1-oxa-4-azonium cyclohexane compounds

ABSTRACT

Novel 1-oxa-4-azonium cyclohexane salts are described. These compounds can be used as structure directing agents, and they overcome many of the typical problems associated with OSDA synthesis and subsequent zeolite synthesis. Methods for synthesis of the 1-oxa-4-azonium cyclohexane salts from a variety of starting materials are also described. A substituted hydrocarbon is added to water to form a mixture, and a 1-oxa-4-azacyclohexane derivative is then added. The reaction mixture stirred until a solution containing the 1-oxa-4-azonium cyclohexane salt is obtained.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation-In-Part of copending U.S. applicationSer. No. 15/334,154 filed Oct. 25, 2016, which application is a Divisionof U.S. application Ser. No. 14/561,132 filed Dec. 4, 2014, now U.S.Pat. No. 9,522,896 issued Dec. 20, 2016, the contents of which citedapplications are hereby incorporated by reference in their entirety.

BACKGROUND OF THE INVENTION 1. Field of the Invention

This invention relates to novel organo-1-oxa-4-azonium cyclohexanecompounds, and a process for preparing the quaternary ammonium salts.The process involves forming 1-oxa-4-azoniumcyclohexane compounds fromsuitable reagents such as a substituted alkane and1-oxa-4-azacyclohexane derivatives.

2. Description of the Related Art

Classes of molecular sieves include crystalline aluminophosphate,silicoaluminophosphate, or metalloaluminophosphate compositions whichare microporous and which are formed from corner sharing AlO_(4/2) andPO_(4/2) tetrahedra. This class is described by Lok and coworkers inU.S. Pat. No. 4,440,871. Other classes of molecular sieves includecrystalline aluminosilicate or silicate compositions, often referred toas zeolites. These are formed from corner sharing SiO_(4/2) andAlO_(4/2) tetrahedra. Numerous molecular sieves, both naturallyoccurring and synthetically prepared, are used in various industrialprocesses. Synthetically, these molecular sieves are prepared viahydrothermal synthesis employing suitable sources of Si, Al, P, andstructure directing agents such as alkali metals, alkaline earth metals,amines, or organoammonium cations. The structure directing agents residein the pores of the molecular sieve and are largely responsible for theparticular structure that is ultimately formed. These species maybalance the framework charge associated with silicon or other metalssuch as Zn in the aluminophosphate compositions or aluminum in thesilicate compositions and can also serve as space fillers to stabilizethe tetrahedral network framework. Molecular sieves are characterized byhaving pore openings of uniform dimensions, having a significant ionexchange capacity, and being capable of reversibly desorbing an adsorbedphase which is dispersed throughout the internal voids of the crystalwithout significantly displacing any atoms which make up the permanentmolecular sieve crystal structure. Molecular sieves can be used ascatalysts for hydrocarbon conversion reactions, which can take place onoutside surfaces as well as on internal surfaces within the pore.

Synthesis of molecular sieve materials often relies on the use oforganoammonium templates known as organic structure directing agents(OSDAs). While simple OSDAs such as tetramethylammonium,tetraethylammonium and tetrapropylammonium are commercially available,often, OSDAs are complicated molecules that are difficult and expensiveto synthesize; however, their importance lies in their ability to impartaspects of their structural features to the molecular sieve to yield adesirable pore structure. For example, the synthesis ofN,N,N,-trimethylmyrtanylammonium derivatives allowed the synthesis ofCIT-1, a member of the CON zeotype (Lobo and Davis J. AM. CHEM. SOC.1995, 117, 3766-79), the synthesis of a methyl substitutedN,N,N′,N′-tetraethylbicyclo[2.2.2]oct-7-ene-2,3,5,6-dipyrrolidiniumdiiodide enabled the synthesis of ITQ-37, the member of the ITV zeotype(Sun, et. al. NATURE, 2009, 458, 1154-7) and synthesis of the transisomer of N,N-diethyl-2-methyldecahydroquinolinium iodide (Elomari, et.al. MICRO. MESO. MATER. 2009, 118, 325-33) allowed synthesis of SSZ-56,the member of the SFS zeotype. The use of1,4,7,10,13,16-hexamethyl-1,4,7,10,13,16-hexaazacyclooctadecane as OSDAhas been shown to allow synthesis of STA-7, an aluminophosphate basedmaterial of the SAV zeotype (Wright, et. al. J. CHEM. SOC., DaltonTrans., 2000, 1243-1248).

The art clearly shows that use of complex organoammonium SDAs oftenresults in new molecular sieve materials. However, the synthesis ofthese complicated organoammonium compounds is quite lengthy and requiresmany steps, often in an organic solvent, thereby hindering developmentof the new molecular sieve material. Frequently, even for simple,commercially available OSDAs, the OSDA is the most costly ingredientused in synthesizing molecular sieve materials. Consequently, it wouldbe economically advantageous to synthesize new molecular sieves fromeither commercially available organoammonium SDAs or SDAs which may bereadily synthesized from commercially available starting materials.

The simple, commercially available, amine morpholine(tetrahydro-1,4-oxazine) has been previously utilized inaluminophosphate based molecular sieve synthesis and has been shown toyield CHA-type molecular sieves (Marchese, et. al. MICRO. MESO. MATER.1999, 30, 145-53; Ito, et. al. ACTA CRYST. 1985, C41, 1698-1700), buthas not yet been shown to yield other structure type molecular sieves.Additionally, the vapor pressure of morpholine is relatively high,making its use on commercial scale troublesome as low vapor pressureorganoammonium SDAs are preferred.

The complicated OSDA(s) discussed previously were synthesized ex-situand added to the reaction mixture at several points. However, onedrawback of ex-situ synthesis is the process is typically carried out inthe presence of an organic solvent, which necessitates at least oneundesirable purification step to recover the SDA from the unwantedorganic material.

Therefore, what is needed in the art are novel organo-1-oxa-4-azoniumcyclohexane compounds. It would be desirable for theseorgano-1-oxa-4-azonium cyclohexane compounds to be useful as SDAs foraluminosilicate, silicate, aluminophosphate, or silicoaluminophosphatecompositions.

SUMMARY OF THE INVENTION

The present invention discloses a process for preparing a pre-reactedaqueous solution of substituted hydrocarbons and amines essentiallyincapable of undergoing pyramidal inversion, which overcomes theaforementioned difficulties. The inventors have made the surprisingdiscovery that a substituted hydrocarbon and amine may be reacted in anaqueous solution at (or slightly above) room temperature to yield anaqueous solution comprising the OSDA. This process is disclosed for abroad class of amines in U.S. application Ser. No. 14/552,654 filed Nov.25, 2014, hereby incorporated by reference now U.S. Pat. No. 9,522,896.This solution may then be used without purification in the synthesis ofmolecular sieves. This procedure thereby allows the preparation of SDAs,such as unusual quaternary ammonium salts, from readily availablestarting reagents in a facile and practical manner.

OSDAs prepared by the methods of the present invention are in aqueoussolution and do not pose odor and flashpoint concerns. The result is theunprecedented ability to remove the cooling step typically required inthe preparation of in-situ zeolite reaction mixtures and to avoidpurification steps such as evaporation of organic solvent typicallyrequired in ex-situ preparation methods.

One aspect of the invention are novel morpholinium compounds comprising1-oxa-4-azonium cyclohexane salts. In one version, the 1-oxa-4-azoniumcyclohexane salts have the structure of Formula 1:

[bis-N,N′-diR₉-(2,2′-diR₁-2,2′-diR₂-3,3′-diR₃-3,3′-diR₄-5,5′-diR₅-5,5′-diR₆-6,6′-diR₇-6,6′-diR₈-1,1′-oxa-4,4′azoniumcyclohexane)-R₁₀]²⁺2X⁻

wherein R₁-R₉ are independently selected from H or an alkyl group havingthe formula C_(n)H_(2n+1), where n is in the range from 1 to 4, X ishalide or hydroxide, the total number of C atoms in the molecule is inthe range of 11 to 24, and R₁₀ is an alkyl group having the formulaC_(m)H_(2m), where m is in the range from 3 to 8 and is connected to the4 and 4′ N atoms at positions x and y of the alkyl chain where x and yare independently selected from 1 to m.

In another aspect, the invention provides a method for synthesizing a1-oxa-4-azonium cyclohexane compound. The method includes the steps of:(a) preparing an aqueous mixture comprising water, a substitutedhydrocarbon and a 1-oxa-4-azacyclohexane derivative; (b) reacting theaqueous mixture; and (c) obtaining a solution comprising theorgano-1-oxa-4-azoniumcyclohexane compound, wherein the mixture and thesolution are essentially free of aluminum and silicon. In one version ofthe method, the solution is essentially free of aluminum, silicon andphosphorous. In one version of the method, the solution is essentiallyfree of aluminum and phosphorous. Essentially free of is meant toindicate that the element described was not intentionally added to themixture or solution. Adventitious amounts of the element may bepermitted, whether coming from dissolution of reactor walls, impuritiesin the starting materials or other causes. Essentially free of maysignify that less than 1 wt % or less than 0.5 wt % or less than 0.1 wt% of the element is present.

In one version of the method, the step of reacting the aqueous mixtureoccurs at a temperature from about 0° C. to about 125° C., and for atime from about 15 min to about 72 hours.

In another version of the method, the organo-1-oxa-4-azoniumcyclohexaneproduct is used as a structure directing agent in the synthesis of amolecular sieve. In another version of the method, the1-oxa-4-azacyclohexane derivative is essentially incapable of undergoingpyramidal inversion.

It is therefore an advantage of the present invention to provide asystem and method for preparing structure directing agents in an aqueousreaction mixture wherein the structure directing agents are prepared inthe absence of Si and Al reactive sources. Furthermore, the aqueousmixture is capable of forming an organo-1-oxa-4-azoniumcyclohexanehalogen salt such as a bromide salt, in order to ultimately provide asolution including a quaternary organoammonium compound. Theorganoammonium bromide salt can be ion-exchanged, either by reactionwith Ag₂O or by anion exchange resins to yield the hydroxide form of theorgano-1-oxa-4-azoniumcyclohexane compound or used as the halogen saltdirectly. Finally, the resultant organoammonium compound can be used forthe synthesis of a zeolite or molecular sieve.

These and other features, aspects, and advantages of the presentinvention will become better understood upon consideration of thefollowing detailed description, drawings and appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustration of the 1-oxa-4-azacyclohexane derivative.

FIG. 2 is an illustration of the class of 1-oxa-4-azonium cyclohexanesalts having the structure of Formula 1.

FIGS. 3A and 3B are illustrations of substituted amine compoundsundergoing pyramidal inversion.

FIG. 4 is an illustration of quaternary ammonium compounds formed from1-oxa-4-azacyclohexane derivatives.

DETAILED DESCRIPTION OF THE INVENTION

The present invention deals with an aqueous process for preparing novel1-oxa-4-azonium cyclohexane salts. These compounds can be used as anorganic structure directing agent (OSDA), and they overcome many of thetypical problems associated with OSDA synthesis and subsequent zeolitesynthesis. Embodiments of the present invention cover methods forsynthesis of the 1-oxa-4-azonium cyclohexane salts from a variety ofstarting materials.

In a typical method for preparing the 1-oxa-4-azonium cyclohexane saltsof the present invention, a substituted hydrocarbon is added to water toform a mixture. The 1-oxa-4-azacyclohexane derivative, as shown in FIG.1, may then be added and the reaction mixture stirred until a solutioncontaining the 1-oxa-4-azonium cyclohexane salt is observed. If thesolution is cooled to room temperature, the product is stably maintainedas an aqueous solution for later use.

In certain embodiments, the precursor reagents (e.g., the substitutedalkane and 1-oxa-4-azacyclohexane derivative) may be added separately ortogether to form the reaction mixture at a number of points in theprocess. The precursors may be reacted together at temperatures rangingfrom about 0° C. to about 125° C. Preferably the precursors are reactedat about room temperature or at a slightly elevated temperature such astemperatures ranging from about 5° C. to about 100° C. More preferably,the precursors are reacted at temperatures from about 20° C. to about120° C., or about 20° C. to about 80° C.

The reaction time varies from about 5 minutes to about 72 hours or fromabout 15 minutes to about 48 hours or from about 30 minutes to about 48hours.

The resulting solution to may be cooled to room temperature or used asis. Other known techniques require the use of purification steps such asdistillation, crystallization, chromatography and removal of a componentvia vacuum. A benefit of the instant method is that the solution of theorgano-1-oxa-4-azoniumcyclohexane salt is prepared without additionalpurification steps occurring prior to use of the solution to makezeolites and molecular sieves. Some small laboratory scale proceduresmay involve removal of unreacted reactants; however, in commercialembodiments, it is most likely to react to completion. Ion-exchange asdescribed below does not purify the solution, but converts halide anionsto hydroxide ions and thus is not a purification step. The resultingsolution may be cooled to room temperature or used as is. However, nopurification steps occur prior to use of the solution.

In one aspect of the present invention, the 1-oxa-4-azonium cyclohexanesalts are prepared from a substituted hydrocarbon and a1-oxa-4-azacyclohexane derivative. α,ω-dihalogen substituted alkaneshaving between 3 and 6 carbon atoms, di-halogen substituted alkaneshaving between 3 and 8 carbon atoms, and combinations thereof. Halogensinclude chlorine, bromine and iodine. In an aspect, the halogen isbromine or iodine. In another aspect, the halogen is bromine. In anaspect, the identity of the halogen substitutions on a substitutedhydrocarbon may be all different, all the same, or any combinationthereof.

α,ω-dihalogen substituted alkanes having between 3 and 6 carbon atomsinclude, but are not limited to, 1,3-dichloropropane,1,4-dichlorobutane, 1,5-dichloropentane, 1,6-dichlorohexane,1,3-dibromopropane, 1,4-dibromobutane, 1,4-dibromo-2-methylbutane,1,5-dibromopentane, 1,6-dibromohexane, 1,3-diiodopropane,1,4-diiodobutane, 1,5-diiodopentane, 1,6-diiodohexane and combinationsthereof.

Di-halogen substituted alkanes having between 3 and 8 carbon atomssuitably include, but are not limited to, 1,2-dibromopropane,1,3-dibromobutane, 1,3-dibromopentane, 1,4-dibromopentane,2,4-dibromopentane, 1,5-dibromohexane, 1,4-dibromohexane,1,3-dibromohexane, 2,4-dibromohexane, 2,5-dibromohexane,2,5-dibromo-3-methylhexane, 2,5-dibromo-3,3-dimethylhexane,1,4-dibromo-2-ethylbutane, and 1,2-dibromo-2-phenylethane. Halogensubstitutions may be chlorine, bromine or iodine, but are illustratedfor bromine. In an aspect, the two halogen substitutions may be the sameor different.

Halogen substitutions may be chlorine, bromine or iodine, but areillustrated for bromine. In an aspect, the identity of the three halogensubstitutions on the substituted hydrocarbon may be all different, allthe same, or any combination thereof.

In an aspect, the mole ratio of the 1-oxa-4-azacyclohexane derivative tothe substitution is from 1:1 to 2:1 and is preferably from 1:1 to 1.5:1.Typically, the mole ratio of 1-oxa-4-azacyclohexane derivative tosubstitution is approximately 1. Thus, when butylbromide is used as thesubstituted hydrocarbon, approximately 1 equivalent of1-oxa-4-azacyclohexane derivative is typically used, whereas when1,4-dibromobutane is used as the substituted hydrocarbon, approximately2 equivalents of 1-oxa-4-azacyclohexane derivative are typically used.

Suitable 1-oxa-4-azacyclohexane derivatives include those for which atleast one conformer is essentially incapable of undergoing pyramidalinversion. The IUPAC definition of pyramidal inversion is given as, “apolytopal rearrangement in which the change in bond directions to athree-coordinate central atom having a pyramidal arrangement of bonds(tripodal arrangement) causes the central atom (apex of the pyramid) toappear to move to an equivalent position on the other side of the baseof the pyramid. If the three ligands to the central atom are differentpyramidal inversion interconverts enantiomers.” The tripodal nature ofmany nitrogen compounds result in the ability of these compounds toundergo pyramidal inversion. Typically, the energy barrier to inversionis low for unconstrained molecules. For example, ammonia (NH₃) has aninversion barrier of 24.5 kJ mol⁻¹, with an observed inversion frequencyof about 2.4*10¹⁰ s⁻¹, dimethylamine has an inversion barrier of 18 kJmol⁻¹, triisopropylamine has an inversion barrier of 6-8 kJ mol⁻¹ anddimethylethylamine has an inversion barrier of 22 kJ mol⁻¹. However,inversion barrier energy can become very high when the nitrogensubstituents are part of a small ring or other rigid molecule as in thecase of 1-methylpyrrolidine. Molecules defined as essentially incapableof undergoing pyramidal inversion have an inversion barrier energy of atleast about 28 kJ mol⁻¹ and more preferably of at least about 30 kJmol⁻¹. A discussion of pyramidal inversion may be found in Rauk, A., etal., (1970), Pyramidal Inversion. ANGEW. CHEM. INT. ED. ENGL., 9:400-414, with further discussion specifically for amines found inINORGANIC CHEMISTRY edited by Arnold F. Holleman, et al., AcademicPress, 2001. Furthermore, FIGS. 3A-B illustrate substituted aminecompounds undergoing pyramidal inversion. Molecules may exist in manyconformers or folding patterns. For example, it is well known that bothchair and boat forms of cyclohexane exist and interconvert between thetwo different conformers. In an aspect of the invention, at least oneconformer of the amine is essentially incapable of undergoing pyramidalinversion.

TABLE 1 Molecules generally incapable of undergoing pyramidal inversion.Inversion Barrier Molecule Name (kJ mol⁻¹) N-methylhomopiperidine 28-291-methyl-4-piperidone 30.7 Trimethylamine 31-351,3,3-trimethylpyrrolidine 31 N-methylpyrrolidine 31-353-methyl-1-thia-3-azacyclopentane 33 9-methyl-9-azabicyclo[3.3.1]nonane34 N-methyl piperidine (equatorial) 36.4 1,2,2,6-tetramethylpiperidine(axial) 38 2-methyl-dihydro-2-azaphenalene 40.5 Methylazetidine 421,2,2,6-tetramethylpiperidine (equitorial) 464-methyl-1-oxa-4-azacyclohexane 48 AKA methylmorpholine2-methyl-1-oxa-2-azacyclohexane (equitorial) 572-methyl-1-oxa-2-azacyclopentane 65 Methylaziridine 80-90

The 1-oxa-4-azacyclohexane derivative is illustrated in FIG. 1 and hasthe structure of formula 1:

2-R₁-2-R₂-3-R₃-3-R₄-4-R₉-5-R₅-5-R₆-6-R₇-6-R₈-1-oxa-4-azacyclohexane,

wherein R₁-R₉ are independently selected from H or an alkyl group havingthe formula C_(n)H_(2n+1), and the total number of C atoms in themolecule is in the range of 4 to 12.

In some versions, R₁-R₉ are H.

In some versions, at least one of R₁-R₉ is an alkyl group. In someversions, at least two of R₁-R₉ are alkyl groups. In some versions, whenat least two of R₁-R₉ are alkyl groups, two of the alkyl groups are onthe same C atom (e.g., R₁ and R₂, or R₃ and R₄, or R₅ and R₆, or R₇ andR₈).

Where more than one alkyl group is present, the alkyl groups can be thesame group or they can be different. Most commonly, the alkyl groups aremethyl or ethyl groups.

The 1-oxa-4-azacyclohexane derivative includes R₁-R₉, and at least R₁₀is from the substituted hydrocarbon. In some versions, the substituentsat R₁-R₈ of the 1-oxa-4-azacyclohexane derivative and the substituentsat R₁-R₈ of the 1-oxa-4-azoniumcyclohexane salt are the same. In someversions, the substituents at R₁-R₉ of the 1-oxa-4-azacyclohexanederivative and the substituents at R₁-R₉ of the1-oxa-4-azoniumcyclohexane salt are the same.

One class of 1-oxa-4-azoniumcyclohexane salts have the structure ofFormula 1:

[bis-N,N′-diR₉-(2,2′-diR₁-2,2′-diR₂-3,3′-diR₃-3,3′-diR₄-5,5′-diR₅-5,5′-diR₆-6,6′-diR₇-6,6′-diR₈-1,1′-oxa-4,4′azoniumcyclohexane)-R₁₀]²⁺2X⁻

wherein R₁-R₉ are independently selected from H or an alkyl group havingthe formula C_(n)H_(2n+1), where n is in the range from 1 to 4, X ishalide or hydroxide, the total number of C atoms in the molecule is inthe range of 11 to 24, and R₁₀ is an alkyl group having the formulaC_(m)H_(2m), where m is in the range from 3 to 8 and is connected to the4 and 4′ N atoms at positions x and y of the alkyl chain where x and yare independently selected from 1 to m.

In some versions, when R₁-R₈ are H, R₉ is CH₃, R₁₀ is C₄H₈, x is 1, andy is 4, X is hydroxide; or when R₁-R₈ are H, R₉ is CH₃, R₁₀ is C₅H₁₀, xis 1, and y is 5, X is hydroxide; or when R₁-R₈ are H, R₉ is CH₃, R₁₀ isC₆H₁₂, x is 1, and y is 6, X is hydroxide; or when R₁-R₈ are H, R₉ isCH₃, R₁₀ is C₇H₁₄, x is 1, and y is 7, X is hydroxide; or when R₁-R₈ areH, R₉ is C₂H₅, R₁₀ is C₆H₁₂, x is 1, and y is 6, X is hydroxide.

In some versions, when R₁-R₈ are H and R₉ is CH₃ or C₂H₅, then X ishydroxide. In some versions, when R₁-R₈ are H and R₉ is CH₃, then m is 3or 8. In some versions, when R₁-R₈ are H and R₉ is C₂H₅, then m is 3, 4,5, 7, or 8. In some versions, when R₁-R₈ are H and R₉ is CH₃, then y isnot equal to m. In some versions, when R₁-R₈ are H and R₉ is C₂H₅, theny is not equal to m. In some versions, when R₁-R₈ are H and R₉ is analkyl group, then y is not equal to m.

In some versions, when R₉ is CH₃ or C₂H₅, then X is hydroxide. In someversions, when R₉ is CH₃, then m is 3 or 8. In some versions, when R₉ isC₂H₅, then m is 3, 4, 5, 7, or 8. In some versions, when R₉ is CH₃, theny is not equal to m. In some versions, when R₉ is C₂H₅, then y is notequal to m. In some versions, when R₉ is an alkyl group, then y is notequal to m.

In some versions, X is hydroxide.

In some versions, R₁₀ is a straight chain alkyl group (i.e., x is 1 andy is m).

In some versions, when R₉ is an alkyl group, X is hydroxide.

In some versions, R₉ is a methyl group. In some versions, R₉ is a methylgroup and R₁₀ has 4 carbons. In some versions, R₉ is a methyl group, R₁₀has 4 carbons, and R₁₀ is attached at the end of the chain to the twomorpholine rings (i.e., x is 1, and y is 4). In some versions, thecompound is a dihalide or a dihydroxide of1,4-bis(4-methylmorpholinium)butane.

In some versions, R₁-R₈ are H. In some versions, when R₁-R₈ are H, R₉ isan alkyl group. In some versions, when R₁-R₈ are H, R₉ is H. In someversions, when R₁-R₈ are H and R₉ is CH₃, y and m do not have the samevalue. In some versions, when R₁-R₈ are H and R₉ is C₂H₅, m is selectedfrom the group consisting of 3, 4, 5, 7, and 8.

In some versions, at least one of R₁-R₈ is an alkyl group. In someversions when at least one of R₁-R₈ is an alkyl group, R₉ is an alkylgroup. In some versions, when at least one of R₁-R₈ is an alkyl group,R₉ is H.

In some versions, at least two of R₁-R₈ are alkyl groups. In someversions, when at least two of R₁-R₈ are alkyl groups, two of the alkylgroups are on the same C atom (e.g., R₁ and R₂, or R₃ and R₄, or R₅ andR₆, or R₇ and R₈).

Where more than one of R₁-R₉ is an alkyl group, the alkyl groups can bethe same group or they can be different. Most commonly, the alkyl groupsare methyl or ethyl groups.

In some versions, the 1-oxa-4-azonium cyclohexane salt comprises atleast one of the di-halides or di-hydroxides of bis-: 4-butylmorpholine,4-propylmorpholine, 4-ethylmorpholine, 4-methylmorpholine, morpholine,2-methylmorpholine, 2,4-dimethylmorpholine, 4-ethyl-2-methylmorpholine,4-propyl-2-methylmorpholine, 3-methylmorpholine, 3,4-dimethylmorpholine,4-ethyl-3-methylmorpholine, 4-propyl-3-methylmorpholine,5-methylmorpholine, 2,5-dimethylmorpholine, 4-ethyl-5-methylmorpholine,4-propyl-5-methylmorpholine, 5-ethyl-2-methylmorpholine,6-methylmorpholine, 4,6-dimethylmorpholine, 4-ethyl-6-methylmorpholine,4-propyl-6-methylmorpholine, 2,6-dimethylmorpholine,2,4,6-trimethylmorpholine, 4-ethyl-2,6-dimethylmorpholine,2,3-dimethylmorpholine, 2,3,4-trimethylmorpholine,4-ethyl-2,3-dimethylmorpholine, 2,5-dimethylmorpholine,2,4,5-trimethylmorpholine, 4-ethyl-2,5-dimethylmorpholine,2,2-dimethylmorpholine, 2,2,4-trimethylmorpholine,4-ethyl-2,2-dimethylmorpholine, 3,3-dimethylmorpholine,3,3,4-trimethylmorpholine, 4-ethyl-3,3-dimethylmorpholine,5,5-dimethylmorpholine, 4,5,5-trimethylmorpholine,4-ethyl-5,5-dimethylmorpholine, 6,6-dimethylmorpholine,4,6,6-trimethylmorpholine, 4-ethyl-6,6-dimethylmorpholine,5-ethyl-2-methylmorpholine and combinations thereof. Butyl may indicaten-butyl, sec-butyl, isobutyl or tert-butyl. Propyl may indicate n-propylor isopropyl.

As an example, FIG. 4 shows the 1,4-bis(4-ethylmorpholinium) butanedibromide product formed from the reaction of 1,4-dibromobutane with4-ethylmorpholinium.

The 1-oxa-4-azonium cyclohexane halide salt can be ion-exchanged, eitherby reaction with Ag₂O yielding AgX as a byproduct or by passage acrossanion exchange resins to yield the hydroxide form of the 1-oxa-4-azoniumcyclohexane compound or used as the halogen salt directly.

The ion-exchange process may involve contacting the 1-oxa-4-azoniumcyclohexane halide salt with an ion-exchange resin having hydroxideions. A particular ion-exchange resin capable of converting halide ionsto hydroxide ions is Dowex Monosphere 550A UPW, available from DowChemical. The ion exchange may take place at temperatures from about 20°C. to about 85° C. or from about 20° C. to about 50° C. or from about25° C. to about 40° C. for times from about 15 minutes to about 8 hoursor from about 30 minutes to about 6 hours or from about 30 minutes toabout 3 hours. The ion exchange may be performed in continuous or batchmode or any combination thereof. Batch mode is preferred when using Ag₂Oand continuous mode is preferred when using ion exchange resin.Individual 1-oxa-4-azonium cyclohexane halide salts may requiredifferent operating conditions for the ion exchange from halide tohydroxide. Depending on the interaction of anion with the1-oxa-4-azonium cyclohexane cation, ion-exchange may be difficult orimpossible.

Comparing the ¹³C chemical shifts for the bromide and hydroxide salts inExample 2 and Example 3 shows that the interaction of the1-oxa-4-azonium cyclohexane_salt with the anion varies with the identityof the anion. In particular, without wishing to be bound to theory, thechemical potential of the C atom next to the cationic N center isparticularly affected. The electron density of the salt can be greatlyaffected by the identity of the anion. This difference can greatlyaffect the ability of the 1-oxa-4-azonium cyclohexane anion salt todirect the synthesis of particular zeolites or molecular sieves. Inmolecular sieve synthesis, hydroxide is typically used as a mineralizingagent, so hydroxide SDA salts are often preferred to halide SDA salts.Utilizing the 1-oxa-4-azonium cyclohexane anion salt as a hydroxide saltalso allows the separation of hydroxide to T-atom ratio, an importantmolecular sieve synthesis parameter, from metal to T-atom ratio as metalions such as sodium are no longer introduced on a 1:1 mole basis withhydroxide. T-atom is used to represent the elements in tetrahedralframework positions, typically silicon, phosphorous or aluminum.

EXAMPLES

In order to more fully illustrate the invention, the following examplesare set forth. It is to be understood that the examples are only by wayof illustration and are not intended as a limitation on the broad scopeof the invention as set forth in the appended claims.

Example 1

422.44 g water was weighed into a 2 L Teflon bottle, and the bottle wasplaced in a 4 L beaker. Under constant stirring, 218.1 g 1,4dibromobutane, 99% was added to the water. To this mixture, 204.34 g4-Methylmorpholine, 99% was added. Approximately 1.5 L tap water wasplaced in the 4 L beaker surrounding the Teflon bottle to help controlthe heat of reaction. Low heat, approximately 50° C., was used to warmup the mixture. Stirring was continued until a yellow solution wasformed and no clear additional phase was present. ¹³C NMR of thesolution showed a ratio of 1 mole methylmorpholine to 2.83 moles1,4-bis(4-methylmorpholinium)butane dibromide.

Example 2

413 g water was weighed into a 2 L Teflon bottle. 474.1 g. 1,5Dibromopentane, 97% (2 moles) was added. To this mixture, 176 g.Morpholine, 99% (4 moles) was added while stirring. The water andmorpholine combined to form a cloudy phase while the denserdibromopentane remained on the bottom. The Teflon bottle was moved intoa 4 liter beaker as secondary containment and placed under a high speedoverhead stirrer for stirring at room temperature. Approximately 1-1.5liters of cool water were added to the 4 liter beaker to disperse astrong exotherm should one occur. At about 15 minutes, the mixture beganto turn yellow, indicating the reaction was beginning. The exotherm wasmild. After an hour, the result was a clear light orange “solution”. Theremaining 413 g water was mixed in to make the final solution. ¹³Cnuclear magnetic resonance (NMR) was used to confirm that the productcomprises a 3-oxa-6-azoniaspiro[5.5]undecane bromide solution. Peaks forthe spirocyclic compound were observed at 63.6, 59.9, 58.0, 21.0, and18.9 ppm with respect to tetramethylsilane. Resonances for morpholiniumwere present at 59.9 and 43.4 ppm. The ratio of spirocyclic compound tomorpholinium was 1:1. Variable temperature NMR, with C—N splitting isrequired to identify both compounds and acquire the proper integrationratios. The starting material 1,5-dibromopentane has peaks at 29.3,34.4, and 36.2 ppm with integral ratios of 1:2:2 respectively which isnot observed in the final solution.

Example 3

1150 grams of the solution from Example 2 was contacted with 336.4 gramsof Ag₂O in a round-bottom flask, which combined to form a grey opaquesolution. The flask was placed under a high speed overheard stirrer forstirring at room temperature (open system) for 1 day. The sample wasfiltered to remove the precipitated silver bromide and the finalsolution was sent for water analysis which showed that the sample wascomposed of 64.6% water. ¹³C nuclear magnetic resonance (NMR) was usedto confirm that the product comprises a 3-oxa-6-azoniaspiro[5.5]undecanehydroxide solution. Peaks for the spirocyclic compound were observed at67.1, 60.0, 57.9, 20.9, and 18.7 ppm with respect to tetramethylsilane.Resonances for morpholinium were present at 59.8 and 44.7 ppm. The ratioof spirocyclic compound to morpholinium was about 1:1. Comparing the ¹³Cchemical shifts for the bromide and hydroxide salts in Example 2 andExample 3 shows that the interaction of the 1-oxa-4-azonium cyclohexanesalt with the anion varies with the identity of the anion. Inparticular, without wishing to be bound to theory, the chemicalpotential of the C atom next to the cationic N center is particularlyaffected. The electron density of the salt can be greatly affected bythe identity of the anion.

Example 4

88.65 g water was weighed into a 1 L Teflon bottle. 141.33 g1,4-Dibromobutane, 99% was added. To this mixture, 154 g4-Ethylmorpholine, 97% was added. The water and ethylmorpholine combinedto form a cloudy phase while the denser dibromobutane remained on thebottom. The Teflon bottle was moved into a 2 liter beaker as secondarycontainment and placed under a high speed overhead stirrer for stirringat room temperature. The Teflon bottle was sealed and placed at 100° C.overnight with no stirring. After the solution was cooled back down toroom temperature, 88 g of deionized water was added to the solution. Thesolution was again placed at 100° C. overnight with no stirring and theresult was a brown translucent solution which, by ¹³C NMR containedpeaks for 1,4-bis(4-ethylmorpholinium) butane dication. The sample wassent for water analysis which showed that it was composed of 36.6%water.

Example 5

355.88 g water was weighed into a 2 L glass beaker. 355.57 g1,5-Dibromopentane, 97% (1.5 moles) was added. To this mixture, 356.19 g4-Ethylmorpholine, 97% (3 moles) was added. The water andethylmorpholine combined to form a cloudy phase while the denserdibromopentane remained on the bottom. The glass beaker was moved onto ahot plate with low heat and placed under a high speed overhead stirrerfor stirring at room temperature. The solution was then transferred intoa 2 L Teflon bottle, which was sealed and placed at 100° C. overnightwith no stirring. After cooling, the solution as placed into a 2 L Parrautoclave and heated to 100° C. for 4 hours. 355.88 g of deionized waterwas then added to obtain a 50% solution.

Example 6

196.5 g, water was weighed into a 2 L Teflon bottle. 254.14 g1,6-Dibromohexane, 96% was added. To this mixture, 204.34 g4-Methylmorpholine, 99% was added. The water and morpholine combined toform a cloudy phase while the denser dibromohexane remained on thebottom. The solution was put in a 4 liter beaker as secondarycontainment and placed under a high speed overhead stirrer for stirringat room temperature. The solution was then transferred into a 2 L Parrautoclave, which was sealed and placed at 125° C. overnight with nostirring. 261.9 g deionized water was then added to obtain a 50%solution and the sample was placed back into the 2 L Parr autoclave at125° C. overnight. The result was a brown clear solution. ¹³C NMR showedpeaks at 65.5, 60.6, 59.7, 47.0, 25.3, and 21.1 ppm in a 1:2:2:1:1:1ratio for 1,6-bis(4-Methylmorpholinium)hexane dibromide and peaks at64.9, 53.9, and 44.5 ppm in a 2:2:1 ratio for starting material4-methylmorpholine. The ratio of diquaternary compound to amine was1:0.9.

Example 7

439 grams of the solution from Example 4 was contacted with 147.5 gramsof Ag₂O in a round-bottom flask, which combined to form a grey opaquesolution. The flask was placed under a high speed overheard stirrer forstirring at room temperature for 1 day. The sample was filtered toremove the precipitated silver bromide and the final solution was sentfor water analysis which showed that the sample was composed of 67.0%water.

Example 8

1257 grams of the solution from Example 5 was contacted with 324.26grams of Ag₂O in a round-bottom flask, which combined to form a greyopaque solution. The flask was placed under a high speed overheardstirrer for stirring at room temperature for 1 day. The sample wasfiltered to remove the precipitated silver bromide and the finalsolution was sent for water analysis which showed that the sample wascomposed of 65.9% water.

Example 9

1116 grams of the solution from Example 6 was contacted with 295.64grams of Ag₂O in a round-bottom flask, which combined to form a greyopaque solution. The flask was placed under a high speed overheardstirrer for stirring at room temperature for 1 day. The sample wasfiltered to remove the precipitated silver bromide and the finalsolution was sent for water analysis which showed that the sample wascomposed of 60.9% water.

Example 10

25.73 g water was weighed into a 125 mL Teflon bottle. 12.57 g1,4-Dibromobutane, 99% was added. To this mixture, 13.15 g2,6-Dimethylmorpholine, 97.1% was added while stirring. The water and2-6-dimethylmorpholine combined to form a cloudy phase while the denserdibromobutane remained on the bottom. The Teflon bottle was moved into a400 mL beaker as secondary containment and placed on a hot plate forstirring under low heat while sealed, approximately 90° C. After twodays, the result was a clear light yellow solution. The sample was sentfor ¹³C NMR. The 1-oxa-4-azonium cyclohexane derivative2,6-dimethylmorpholine is comprised of two compounds, A having peaks at75.5, 55.1, and 21.9 ppm with 1:1:1 ratios and B having peaks at 69.1,54.2, and 20.5 ppm with 1:1:1 ratios. The ratio of the two compounds is2.75 A to 1B. The yellow solution has peaks at 16.4, 17.2, 17.3, 17.7,20.6, 21.0, 21.7, 46.5, 47.2, 59.4, 61.7, 63.0, 63.9, 64.0, 65.7, 68.1,68.3 and 69.8 ppm with integral ratios of 1.25, 1.75, 3.7, 4, 1.2, 4.1,2, 1.8, 4.35, 1.3, 1.5, 1.8, 4, 1.95, and 4 respectively. Withoutwishing to be bound by theory, it is believed that compounds A and B inthe morpholine derivative are the cis and trans forms of the2,6-dimethylmorpholine and peaks in the product are due to multipleconformers of cis and trans substituted dimethylmorpholine based salts.

Example 11

591.15 g water was weighed into a 2 L Teflon bottle. 436.21 g1,4-Dibromobutane, 99% (2 moles) was added. To this mixture, 352.0 gMorpholine, 99% (4 moles) was added while stirring. The water andmorpholine combined to form a cloudy phase while the denserdibromobutane remained on the bottom. The Teflon bottle was moved into a4 liter beaker as secondary containment and placed under a high speedoverhead stirrer for stirring at room temperature. Approximately 0.5-1liters of cool water were added to the 4 liter beaker to disperse astrong exotherm should one occur. After 1.5-2.5 hours, the result was aclear light yellow solution. An additional 197.05 g water was mixed into form the final solution. ¹³C nuclear magnetic resonance (NMR) wasused to confirm that the product was a 8-oxa-5-azoniaspiro[4.5]decanebromide solution. Peaks for the spirocyclic compound were observed at63.3, 62.3, 59.2, and 21.4 ppm with respect to tetramethylsilane withintegral ratios of 2:2:2:2 respectively. Resonances for morpholiniumwere present at 63.9 and 43.5 ppm with integral ratios of 2:2. The ratioof spirocyclic compound to morpholinium was 1:1. The presence of bothcompounds was confirmed by ion chromatography/mass spectrometry. Thestarting material 1,4-dibromobutane has peaks in the ¹³C NMR at 33.5 and35.5 ppm. Peaks due to the dibromobutane were not observed in the finalsolution.

Example 12

1200 grams of the solution from Example 6 was contacted with 365.5 gramsof Ag₂O in a round-bottom flask, which combined to form a grey opaquesolution. The flask was placed under a high speed overheard stirrer forstirring at room temperature for 1 day. The sample was filtered toremove the precipitated silver bromide and the final solution was sentfor water analysis which showed that the sample was composed of 67.3%water.

Although the invention has been described in considerable detail withreference to certain embodiments, one skilled in the art will appreciatethat the present invention can be practiced by other than the describedembodiments, which have been presented for purposes of illustration andnot of limitation. Therefore, the scope of the appended claims shouldnot be limited to the description of the embodiments contained herein.

1. A morpholinium compound comprising a 1-oxa-4-azonium cyclohexane salthaving a structure of:

wherein R₁-R₉ are independently selected from H or an alkyl group havingthe formula C_(n)H_(2n+1), where n is in the range from 1 to 4, X ishalide or hydroxide, the total number of C atoms in the molecule is inthe range of 11 to 24, and R₁₀ is an alkyl group having the formulaC_(m)H_(2m), where m is in the range from 3 to 8 and is connected to the4 and 4′ N atoms at positions x and y of the alkyl chain where x and yare independently selected from 1 to m; with the proviso that: whenR₁-R₈ are H, R₉ is CH₃, R₁₀ is C₄H₈, x is 1, and y is 4, X is hydroxide;or when R₁-R₈ are H, R₉ is CH₃, R₁₀ is C₅H₁₀, x is 1, and y is 5, X ishydroxide; or when R₁-R₈ are H, R₉ is CH₃, R₁₀ is C₆H₁₂, x is 1, and yis 6, X is hydroxide; or when R₁-R₈ are H, R₉ is CH₃, R₁₀ is C₇H₁₄, x is1, and y is 7, X is hydroxide; or when R₁-R₈ are H, R₉ is C₂H₅, R₁₀ isC₆H₁₂, x is 1, and y is 6, X is hydroxide.
 2. The morpholinium compoundof claim 1 wherein X is hydroxide.
 3. The morpholinium compound of claim1 wherein R₁-R₈ are H.
 4. The morpholinium compound of claim 1 whereinat least one of R₁-R₈ is an alkyl group.
 5. The morpholinium compound ofclaim 1 wherein x is 1, and y is m.
 6. The morpholinium compound ofclaim 1 wherein when R₉ is an alkyl group and X is hydroxide.
 7. Themorpholinium compound of claim 1 wherein R₉ is an alkyl group and n is1, m is 4, x is 1, and y is
 4. 8. The morpholinium compound of claim 1wherein at least two of R₁-R₈ are the alkyl group, and wherein the atleast two of R₁-R₈ are R₁ and R₂, or R₃ and R₄, or R₅ and R₆, or R₇ andR₈.
 9. The morpholinium compound of claim 1 wherein at least two ofR₁-R₈ are an alkyl group, and wherein at least two of R₁-R₈ are the samealkyl group.
 10. A method for synthesizing a 1-oxa-4-azonium cyclohexanesalt, comprising: preparing an aqueous mixture comprising water, asubstituted hydrocarbon, and a 1-oxa-4-azacyclohexane derivative;reacting the aqueous mixture; obtaining a solution comprising the1-oxa-4-azonium cyclohexane salt; and wherein the mixture and thesolution are essentially free of aluminum and silicon.